But those protections left officers at the jail without fear of sanctions for allegedly smuggling contraband or having relationships with inmates, the FBI said in an affidavit made public this week. They said internal sanctions were "ineffective as a deterrent" for dealing with gangs.

Officers suspected of violations were often transferred to another facility inside the jail complex, according to the affidavit.

"It ain't nothing new," officer Kimberly Dennis told an alleged co-conspirator, according to a summary of a recorded call. "I got moved over there basically because I'm dirty."

Dennis' attorney, Joseph Murtha, declined to comment on the allegations.

Archer Blackwell, a representative for the detention center's corrections officer union, said the process protects employees. "It's no better or worse than any [administrative] procedure where people are afforded certain rights," he said.

The officers' alleged role in building up the power of the Black Guerrilla Family gang inside the jail is the focus of a federal racketeering, money-laundering and drug indictment. Thirteen women employed at the jail are accused of supporting the criminal enterprise of gang leader Tavon White.

The group of female corrections officers was hired between 2005 and 2011, according to the Maryland Department of Public Safety and Correctional Services, which runs the jail. Officers are paid from $36,000 to around $47,000 per year.

Corrections officers are hired through a central unit in the department, according to the FBI affidavit. Since 2010, part of the hiring process has included checking for gang affiliations.

If candidates pass a background check, medical tests and psychological screening, they are assigned to a jail or prison based on vacant positions and their preference. New hires get 35 days of training, according to the department. That course includes "an intensive focus on corruption including classes on … fraternization," according to the department.

Officers indicted for felonies can be suspended without pay, as the 13 accused in the federal case have been.

The indictment brought fresh attention to the high numbers of female corrections officers at a detention facility that primarily houses men. More than 60 percent of the corrections officers at the Baltimore City Detention Center are women, according to the department.

New gang members receive a manual instructing them to target officers "with low self-esteem, insecurities, and certain physical attributes," according to the affidavit in the federal case.

Federal prosecutors alleged in the indictment that gang members used sexual relationships to maintain bonds with corrections officers and further their criminal activities. White allegedly got four of the officers pregnant and has two children with one of them, according to the affidavit.

It is a misdemeanor for a Maryland corrections officer to have sex with an inmate; the crime is punishable by three years in prison and a $3,000 fine.

Sen. Lisa Gladden, a Baltimore Democrat who works as a public defender, said that the corrections culture must change and that more men should be guarding male inmates, removing sexual temptations for guards.

"When you hire and seek women to handle men, you get all sorts of crazy stuff," Gladden said. "You cannot allow women to get involved with these men, or you're going to get what you're going to get. You have got to find a way to make sure that what the guards need is not something that the inmates can give, if you know what I mean."

She suggested the prison system could discourage such relationships by requiring college degrees for corrections officers.

"If you had college graduates, four-year graduates, do you think they're going to be messing around with a guy who dropped out of high school?"

Federal authorities charge that Tavon White, an inmate known as "Bulldog," took control of the Black Guerrilla Family gang at the Baltimore City Detention Center soon after his arrival in 2009 on an attempted murder charge. He is seen here in a 2009 mug shot from the Anne Arundel County Police...